Simon Wunderlich says:
====================
Here are two batman-adv bugfixes:
- Keep fragments equally sized, avoids some problems with too small fragments,
by Sven Eckelmann
- Initialize gateway class correctly when BATMAN V is compiled in,
by Sven Eckelmann
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The gateway selection class variable is shared between different algorithm
versions. But the interpretation of the content is algorithm specific. The
initialization is therefore also algorithm specific.
But this was implemented incorrectly and the initialization for BATMAN_V
always overwrote the value previously written for BATMAN_IV. This could
only be avoided when BATMAN_V was disabled during compile time.
Using a special batadv_algo hook for this initialization avoids this
problem.
Fixes: 50164d8f50 ("batman-adv: B.A.T.M.A.N. V - implement GW selection logic")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Declaring the factor is counter-intuitive, and people are prone
to using small(-ish) values even when that makes no sense.
Change the DECLARE_EWMA() macro to take the fractional precision,
in bits, rather than a factor, and update all users.
While at it, add some more documentation.
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In rare cases during shutdown the following general protection fault can
happen:
general protection fault: 0000 [#1] SMP
Modules linked in: batman_adv(O-) [...]
CPU: 3 PID: 1714 Comm: rmmod Tainted: G O 4.6.0-rc6+ #1
[...]
Call Trace:
[<ffffffffa0363294>] batadv_hardif_disable_interface+0x29a/0x3a6 [batman_adv]
[<ffffffffa0373db4>] batadv_softif_destroy_netlink+0x4b/0xa4 [batman_adv]
[<ffffffff813b52f3>] __rtnl_link_unregister+0x48/0x92
[<ffffffff813b9240>] rtnl_link_unregister+0xc1/0xdb
[<ffffffff8108547c>] ? bit_waitqueue+0x87/0x87
[<ffffffffa03850d2>] batadv_exit+0x1a/0xf48 [batman_adv]
[<ffffffff810c26f9>] SyS_delete_module+0x136/0x1b0
[<ffffffff8144dc65>] entry_SYSCALL_64_fastpath+0x18/0xa8
[<ffffffff8108aaca>] ? trace_hardirqs_off_caller+0x37/0xa6
Code: 89 f7 e8 21 bd 0d e1 4d 85 e4 75 0e 31 f6 48 c7 c7 50 d7 3b a0 e8 50 16 f2 e0 49 8b 9c 24 28 01 00 00 48 85 db 0f 84 b2 00 00 00 <48> 8b 03 4d 85 ed 48 89 45 c8 74 09 4c 39 ab f8 00 00 00 75 1c
RIP [<ffffffffa0371852>] batadv_purge_outstanding_packets+0x1c8/0x291 [batman_adv]
RSP <ffff88001da5fd78>
---[ end trace 803b9bdc6a4a952b ]---
Kernel panic - not syncing: Fatal exception in interrupt
Kernel Offset: disabled
---[ end Kernel panic - not syncing: Fatal exception in interrupt
It does not happen often, but may potentially happen when frequently
shutting down and reinitializing an interface. With some carefully
placed msleep()s/mdelay()s it can be reproduced easily.
The issue is, that on interface removal, any still running worker thread
of a forwarding packet will race with the interface purging routine to
free a forwarding packet. Temporarily giving up a spin-lock to be able
to sleep in the purging routine is not safe.
Furthermore, there is a potential general protection fault not just for
the purging side shown above, but also on the worker side: Temporarily
removing a forw_packet from the according forw_{bcast,bat}_list will make
it impossible for the purging routine to catch and cancel it.
# How this patch tries to fix it:
With this patch we split the queue purging into three steps: Step 1),
removing forward packets from the queue of an interface and by that
claim it as our responsibility to free.
Step 2), we are either lucky to cancel a pending worker before it starts
to run. Or if it is already running, we wait and let it do its thing,
except two things:
Through the claiming in step 1) we prevent workers from a) re-arming
themselves. And b) prevent workers from freeing packets which we still
hold in the interface purging routine.
Finally, step 3, we are sure that no forwarding packets are pending or
even running anymore on the interface to remove. We can then safely free
the claimed forwarding packets.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
In a few situations batman-adv tries to determine whether a given interface
is a WiFi interface to enable specific WiFi optimizations. If the interface
batman-adv has been configured with is a virtual interface (e.g. VLAN) it
would not be properly detected as WiFi interface and thus not benefit from
the special WiFi treatment.
This patch changes that by peeking under the hood whenever a virtual
interface is in play.
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
[sven.eckelmann@open-mesh.com: integrate in wifi_flags caching, retrieve
namespace of link interface]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
batman-adv is requiring the type of wifi device in different contexts. Some
of them can take the rtnl semaphore and some of them already have the
semaphore taken. But even others don't allow that the semaphore will be
taken.
The data has to be retrieved when the hardif is added to batman-adv because
some of the wifi information for an hardif will only be available with rtnl
lock. It can then be cached in the batadv_hard_iface and the functions
is_wifi_netdev and is_cfg80211_netdev can just compare the correct bits
without imposing extra locking requirements.
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
With this patch, (re)broadcasting on a specific interfaces is avoided:
* No neighbor: There is no need to broadcast on an interface if there
is no node behind it.
* Single neighbor is source: If there is just one neighbor on an
interface and if this neighbor is the one we actually got this
broadcast packet from, then we do not need to echo it back.
* Single neighbor is originator: If there is just one neighbor on
an interface and if this neighbor is the originator of this
broadcast packet, then we do not need to echo it back.
Goodies for BATMAN V:
("Upgrade your BATMAN IV network to V now to get these for free!")
Thanks to the split of OGMv1 into two packet types, OGMv2 and ELP
that is, we can now apply the same optimizations stated above to OGMv2
packets, too.
Furthermore, with BATMAN V, rebroadcasts can be reduced in certain
multi interface cases, too, where BATMAN IV cannot. This is thanks to
the removal of the "secondary interface originator" concept in BATMAN V.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Instead of latching onto the OGM period, this patch introduces a worker
dedicated to multicast TT and TVLV updates.
The reasoning is, that upon roaming especially the translation table
should be updated timely to minimize connectivity issues.
With BATMAN V, the idea is to greatly increase the OGM interval to
reduce overhead. Unfortunately, right now this could lead to
a bad user experience if multicast traffic is involved.
Therefore this patch introduces a fixed 500ms update interval for
multicast TT entries and the multicast TVLV.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The batman-adv codebase is using "list" for the list node (prev/next) and
<list content descriptor>+"_list" for the head of a list. Not using this
naming scheme can up in confusions when reading the code.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The batman-adv codebase is using "list" for the list node (prev/next) and
<list content descriptor>+"_list" for the head of a list. Not using this
naming scheme can up in confusions because list_head is used for both the
head of the list and the list node (prev/next) in each item of the list.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The files provided by batman-adv via debugfs are currently converted to
netlink. Tools which are not yet converted to use the netlink interface may
still rely on the old debugfs files. But systems which already upgraded
their tools can save some space by disabling this feature. The default
configuration of batman-adv on amd64 can reduce the size of the module by
around 11% when this feature is disabled.
$ size net/batman-adv/batman-adv.ko*
text data bss dec hex filename
150507 10395 4160 165062 284c6 net/batman-adv/batman-adv.ko.y
137106 7099 2112 146317 23b8d net/batman-adv/batman-adv.ko.n
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Add BATADV_CMD_GET_GATEWAYS commands, using handlers bat_gw_dump in
batadv_algo_ops. Will always return -EOPNOTSUPP for now, as no
implementations exist yet.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Add BATADV_CMD_GET_ORIGINATORS and BATADV_CMD_GET_NEIGHBORS commands,
using handlers bat_orig_dump and bat_neigh_dump in batadv_algo_ops. Will
always return -EOPNOTSUPP for now, as no implementations exist yet.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[sven@narfation.org: Rewrite based on new algo_ops structures]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
This patch abstracts the forward packet creation into the new function
batadv_forw_packet_alloc().
The queue counting and interface reference counters are now handled
internally within batadv_forw_packet_alloc() and its
batadv_forw_packet_free() counterpart. This should reduce the risk of
having reference/queue counting bugs again and should increase
code readibility.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Each routing protocol may have its own specific logic about
gateway election which is potentially based on the metric being
used.
Create two GW specific API functions and move the current election
logic in the B.A.T.M.A.N. IV specific code.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The B.A.T.M.A.N. V algorithm uses a different metric compared to its
predecessor and for this reason the logic used to compute the best
Gateway is also changed. This means that the GW selection class
fed to this logic has a semantics that depends on the algorithm being
used.
Make the parsing and printing routine of the GW selection class
routing algorithm specific. Each algorithm can now parse (and print)
this value independently.
If no API is provided by any algorithm, the default is to use the
current mechanism of considering such value like an integer between
1 and 255.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Postponing the removal of the interface breaks the expected behavior of
NETDEV_UNREGISTER and NETDEV_PRE_TYPE_CHANGE. This is especially
problematic when an interface is removed and added in quick succession.
This reverts commit 5bc44dc845 ("batman-adv: postpone sysfs removal when
unregistering").
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The legacy sysfs interface to modify interfaces belonging to batman-adv
is run inside a region holding s_lock. And to add a net_device, it has
to also get the rtnl_lock. This is exactly the other way around than in
other virtual net_devices and conflicts with netdevice notifier which
executes inside rtnl_lock.
The inverted lock situation is currently solved by executing the removal
of netdevices via workqueue. The workqueue isn't executed inside
rtnl_lock and thus can independently get the s_lock and the rtnl_lock.
But this workaround fails when the netdevice notifier creates events in
quick succession and the earlier triggered removal of a net_device isn't
processed in the workqueue before the adding of the new netdevice (with
same name) event is issued.
Instead the legacy sysfs interface store events have to be enqueued in
a workqueue to loose the s_lock. The worker is then free to get the
required locks and the deadlock is avoided.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Some operations in batadv_algo_ops are optional and marked as such in the
kerneldoc. But some of them miss the "(optional)" in their kerneldoc. These
have to also be marked to give an implementor of an algorithm the correct
background information without looking in the code calling these function
pointers.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The replacement of last_bonding_candidate in batadv_orig_node has to be an
atomic operation. Otherwise it is possible that the reference counter of a
batadv_orig_ifinfo is reduced which was no longer the
last_bonding_candidate when the new candidate is added. This can either
lead to an invalid memory access or to reference leaks which make it
impossible to an interface which was added to batman-adv.
Fixes: f3b3d90189 ("batman-adv: add bonding again")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The pointer batadv_bla_claim::backbone_gw can be changed at any time.
Therefore, access to it must be protected to ensure that two function
accessing the same backbone_gw are actually accessing the same. This is
especially important when the crc_lock is used or when the backbone_gw of a
claim is exchanged.
Not doing so leads to invalid memory access and/or reference leaks.
Fixes: 23721387c4 ("batman-adv: add basic bridge loop avoidance code")
Fixes: 5a1dd8a477 ("batman-adv: lock crc access in bridge loop avoidance")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
David S. Miller
Sven Eckelmann
Johannes Berg
Linus Lüssing
Marek Lindner
Sven Eckelmann
Matthias Schiffer
Antonio Quartulli